The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 08, 1994
Filed:
Apr. 26, 1993
Applicant:
Inventors:
Assignee:
ISP Investments Inc., Wilmington, DE (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C08F / ; C08F / ;
U.S. Cl.
CPC ...
5253269 ; 526212 ;
Abstract
A process for making a solution of PVP K-90 polymer having a weight average molecular weight, Mw, of about 630,000 to 750,000 and a molecular weight distribution, Mw/Mn, where Mn is the number average molecular weight of the polymer, of 5 or less, which comprises free radical polymerizing about 5-30% by weight vinylpyrrolidone, preferably 10-20%, at about 40.degree.-100.degree. C., preferably 60.degree.-75.degree. C., in an aqueous-alcohol solvent selected from the group consisting of about (a) 5% isopropanol-95% water, (b) 10% ethanol-90% water and (c) 20% methanol-80% water.